What's in store for North Carolina's fracking future?

Published: Sunday, March 17, 2013 at 4:30 a.m.

Last Modified: Sunday, March 17, 2013 at 4:30 a.m.

Lifting a statewide ban on deep injection wells for contaminated wastewater could have implications beyond just the fracking industry, experts say.

“There are a lot of industries that would like to inject waste into the ground here on the Coastal Plain,” said Charlie Stehman, a retired professional geologist and former supervisor of the state Division of Water Quality's Aquifer Protection Section. “Not just industry, but municipal wastewater systems. There are aquifers in Sanford and closer to Fayetteville that probably could accept waste, but the legislation right now says that no injection can take place.”

The statewide ban, in place for roughly 40 years, was passed after injection wells used by an industrial company in New Hanover County leached contaminants into surrounding groundwater supplies. Hercules, which manufactured raw materials used to produce polyester fabrics, drilled a handful of deep injection wells off U.S. 421, about four miles outside Wilmington.

The Hercules lesson

From 1968 to 1972, the company pumped hundreds of thousands of gallons of terephthalic acid into the wells each day, culminating in unsustainably high pressure underground that caused them to fail.

“Pressures rose so high they just couldn't force any more stuff into the ground,” Stehman said. “They switched to another well, which I believe was a monitoring well, and were pushing stuff into that one. That one over-pressured as well, and then they switched to a third one and finally gave up.”

But not before damage was done. State officials later found that the chemicals had leached into the area's upper aquifers, a discovery that led to the state's current ban on that type of deep injection wells. Legislators in Raleigh are now seeking to repeal that measure, potentially allowing fracking companies to blast for natural gas in the Piedmont region, then truck the contaminated wastewater byproduct to the coast and once more inject it underground.

“In the Senate fracking bill, they had a provision that lifted the ban on injection wells,” said freshman Rep. Rick Catlin, R-New Hanover, one of a handful of legislators who have voiced concerns over the provision. “Hercules really became the poster child for not doing this. You don't have to inject the wastewater. You can treat it, either by placing it in evaporation ponds or by a treatment process, but from the oil companies' perspective, injection is probably the least expensive way to do it.”

Untested theory

Theoretically, the Coastal Plain, composed of porous sediments and soft, semi-consolidated rock like limestone, would be the most logical place in the state for injection wells to be placed. Within that plain, layers are thickest near Hatteras, according to Paul Thayer, professor emeritus of geology at the University of North Carolina Wilmington.

“As you go in a seaward direction, the thickness increases. As you get deeper, towards the base of that, all of those layers tend to be filled with saltwater,” he said. “Potentially, if those saltwater layers were isolated from the overlying layers that might contain freshwater, it would be possible to inject things into the deep subsurface.”

But no detailed studies have ever been conducted to confirm that hypothesis, he said.

“That would be absolutely necessary,” Thayer said. “You've got to have detailed studies ahead of time before you willy-nilly start putting stuff into the ground.”

If the injection well ban stands, it's unclear what, if any, fracking side effects could make their way to the coast. There's an off-chance, Stehman said, that if fracking took place in or near the Deep River, a 125-mile-long Cape Fear River tributary north of Sanford, some contaminants could make their way into Wilmington's watershed, though the likelihood of that possibility is unclear.

“It's probably not a great potential, but it's certainly something one would have to look into,” he said.

Catlin, a hydrogeologist and environmental engineer, was more optimistic.

“Injection wells, from a coastal perspective, are most concerning,” he said. “I doubt there would be any other direct impact on the coast. But it needs to be studied.”

<p>Lifting a statewide ban on deep injection wells for contaminated wastewater could have implications beyond just the fracking industry, experts say.</p><p>“There are a lot of industries that would like to inject waste into the ground here on the Coastal Plain,” said Charlie Stehman, a retired professional geologist and former supervisor of the state Division of Water Quality's Aquifer Protection Section. “Not just industry, but municipal wastewater systems. There are aquifers in Sanford and closer to Fayetteville that probably could accept waste, but the legislation right now says that no injection can take place.”</p><p>The statewide ban, in place for roughly 40 years, was passed after injection wells used by an industrial company in New Hanover County leached contaminants into surrounding groundwater supplies. Hercules, which manufactured raw materials used to produce polyester fabrics, drilled a handful of deep injection wells off U.S. 421, about four miles outside Wilmington.</p><h3>The Hercules lesson</h3>
<p>From 1968 to 1972, the company pumped hundreds of thousands of gallons of terephthalic acid into the wells each day, culminating in unsustainably high pressure underground that caused them to fail.</p><p>“Pressures rose so high they just couldn't force any more stuff into the ground,” Stehman said. “They switched to another well, which I believe was a monitoring well, and were pushing stuff into that one. That one over-pressured as well, and then they switched to a third one and finally gave up.”</p><p>But not before damage was done. State officials later found that the chemicals had leached into the area's upper aquifers, a discovery that led to the state's current ban on that type of deep injection wells. Legislators in Raleigh are now seeking to repeal that measure, potentially allowing fracking companies to blast for natural gas in the Piedmont region, then truck the contaminated wastewater byproduct to the coast and once more inject it underground.</p><p>“In the Senate fracking bill, they had a provision that lifted the ban on injection wells,” said freshman Rep. Rick Catlin, R-New Hanover, one of a handful of legislators who have voiced concerns over the provision. “Hercules really became the poster child for not doing this. You don't have to inject the wastewater. You can treat it, either by placing it in evaporation ponds or by a treatment process, but from the oil companies' perspective, injection is probably the least expensive way to do it.”</p><h3>Untested theory</h3>
<p>Theoretically, the Coastal Plain, composed of porous sediments and soft, semi-consolidated rock like limestone, would be the most logical place in the state for injection wells to be placed. Within that plain, layers are thickest near Hatteras, according to Paul Thayer, professor emeritus of geology at the University of North Carolina Wilmington.</p><p>“As you go in a seaward direction, the thickness increases. As you get deeper, towards the base of that, all of those layers tend to be filled with saltwater,” he said. “Potentially, if those saltwater layers were isolated from the overlying layers that might contain freshwater, it would be possible to inject things into the deep subsurface.”</p><p>But no detailed studies have ever been conducted to confirm that hypothesis, he said.</p><p>“That would be absolutely necessary,” Thayer said. “You've got to have detailed studies ahead of time before you willy-nilly start putting stuff into the ground.”</p><p>If the injection well ban stands, it's unclear what, if any, fracking side effects could make their way to the coast. There's an off-chance, Stehman said, that if fracking took place in or near the Deep River, a 125-mile-long <a href="http://www.starnewsonline.com/section/topic91"><b>Cape Fear River</b></a> tributary north of Sanford, some contaminants could make their way into Wilmington's watershed, though the likelihood of that possibility is unclear.</p><p>“It's probably not a great potential, but it's certainly something one would have to look into,” he said.</p><p>Catlin, a hydrogeologist and environmental engineer, was more optimistic.</p><p>“Injection wells, from a coastal perspective, are most concerning,” he said. “I doubt there would be any other direct impact on the coast. But it needs to be studied.”</p><p><i></p><p>Kate Elizabeth Queram: 343-2217</p><p>On <a href="http://www.starnewsonline.com/section/news41"><b>Twitter</b></a>: @kate_goes_bleu</i></p>